Heated Floor Panel For Transit Vehicle

ABSTRACT

A system for generating radiant heat in a transit vehicle includes at least one floor panel having at least one heating element disposed therein, and a power switch operably disposed intermediate a power supply source and the heating element for selectively providing and discontinuing a supply of predetermined power generated by such power supply source to and from such at least one heating element.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 11/374,917filed on Mar. 14, 2006. Priority is claimed.

FIELD OF THE INVENTION

The present invention relates, in general, to floor panels and, moreparticularly, this invention relates to electrically heated compositefloor panels and, yet more particularly the instant invention relates toelectrically heated composite floor panels for transit vehicle.

BACKGROUND OF THE INVENTION

As is generally well known, heating of a passenger compartment in atransit vehicle is achieved by a combination of several heatingcomponents. One heating component, which is known as a conventionalbaseboard electric heater, is installed longitudinally and in series oneach side of the transit vehicle either at a juncture of the floor andthe side wall or directly within the side wall and being somewhatelevated from the floor of the vehicle. Mounting of the baseboardheaters is interrupted by the side doors located within each side wallof the transit vehicle and which are used for passenger ingress andegress. The actual finned electric heating element is positioned behinda grill mesh that enables the generated heat to flow into the seatingarea. Baseboard heaters generate about forty percent of the requiredtotal heating energy. Additionally, the heat generated by baseboardheaters may be routed, by way of convection, within the side walls forentering the passenger compartment through the grills generallypositioned slightly below the bottom edge of the side window.

Another heating component is mounted in series on the roof of thetransit vehicle with generated heat being forced in a downward fashionvia blowers into the passenger compartment from the grills positionedwithin or near a ceiling of such transit vehicle. Such roof mountedheaters generate remaining sixty percent of the total heating energy.

There are number of disadvantages of using baseboard heaters for heatingpassenger compartment of the transit vehicle.

Such heaters occupy between about ten and about twelve percent of thevehicle width thus reducing the actual usable space of the passengercompartment.

Use of stainless steel enclosures and finned electrical heating elementsincrease the installation costs, particularly in vehicles wherein theheating elements are mounted within the side wall and require structuralsupports which further increase the weight of the vehicle.

Baseboard heating elements typically operate at a temperature betweenabout 400 degrees Fahrenheit and about 500 degrees Fahrenheit. Grillsare positioned to maintain surface temperature of less than 125 degreesFahrenheit as mandated by Americans With Disability Act (ADA). However,such baseboard heaters have been regarded as fire hazards due to theoften close proximity of flammable items such as clothing, coats, babyblankets, briefcases, and the like. A heat transfer loss occurs throughthe portion of the side wall containing such baseboard heaters due tolack of insulation.

Baseboard heaters generally require the use of stainless steelenclosures and grills due to harsh chemicals being used in floorcleaning, which increases the installation costs.

Floor areas disposed adjacent each side door used for passenger ingressand egress are poorly heated, resulting in frequent floor structurefailures due to moisture, such as rain, snow and sleet, entering thetransit vehicle when doors are opened and as passengers ingress andegress the vehicle. Accordingly, door threshold heaters, when employed,must be designed to heat a portion of the vehicle adjacent to each sidedoor resulting in increased manufacturing costs.

The baseboard heaters do not generally heat a portion of the floor,which is disposed along the longitudinal centerline of the transitvehicle and is further disposed between the seats. Standing passengerswhich use such portion of the floor _(a)re standing on a colder floorsurface. It has been proven that a person experiences bodily warmth ifones feet are warmed despite a cool ambient temperature. Accordingly,higher heat energy must be generated from roof mounted heaters tocompensate for this condition.

Therefore, there is a need for an improved system for at least partiallyheating passenger compartment of the transit vehicle.

SUMMARY OF THE INVENTION

According to a first embodiment of the invention, varying is provided afloor panel for a transit vehicle which includes a core having each ofthe predetermined size and a predetermined shape and a bottom skinrigidly attached to one surface of the core. At least one heatingelement has each of the predetermined size and a predetermined shape andis positioned within a respective groove formed in an opposed surface ofthe core. A top of the at least one heating element is essentially flushwith the opposed surface. Ends of the at least one heating element areexposed within a cavity formed in a predetermined location of such floorpanel. A top skin is rigidly attached to the opposed surface of thecore.

According to a second embodiment, the invention provides a system Forgenerating radiant heat in a transit vehicle. Such system includes atleast one floor panel having a predetermined shape and a predeterminedsize and having at least one heating element disposed therein a powerswitch is operably disposed intermediately to a power supply source ofsuch transit vehicle and the at least one heating element forselectively providing and discontinuing a supply of a predeterminedpower generated by such power supply source to the at least one heatingelement.

According to a third embodiment, the present invention provides a methodfor generating radiant heat in a transit vehicle. The method includesthe steps of installing at least one floor panel having at least oneheating element disposed therein, connecting the at least one heatingelement to a power switch, then connecting the power switch to a powersource of such transit vehicle capable of supplying a predeterminedpower, and selectively operating the power switch to provide anddiscontinue a supply of the predetermined power to the at least oneheating element.

OBJECTS OF THE INVENTION

It is, therefore, one of the primary objects of the present invention toprovide a system for generating even radiant heating within thepassenger compartment of the transit vehicle.

Another object of the present invention is to provide a system forgenerating radiant heat within the passenger compartment of the transitvehicle that employs floor panels having a heating element disposedtherein.

Yet another object of the present invention is to provide a system forgenerating radiant heat within the passenger compartment of the transitvehicle employing heated floor panels that are simpler to install thanconventional baseboard heaters.

A further object of the present invention is to provide a system forgenerating radiant heat within the passenger compartment of the transitvehicle employing heated floor panels which adequately control surfacetemperature and do not pose fire hazards.

Yet, a further object of the present invention is to provide a systemfor generating radiant heat within the passenger compartment of thetransit vehicle employing heated floor panels that is responsive tofluctuating interior and ambient temperatures.

An additional object of the present invention is to provide a system forgenerating radiant heat within the passenger compartment of the transitvehicle employing heated composite floor panels.

In addition to the several objects and advantages of the presentinvention which have been described with some degree of specificityabove, various other objects and advantages of the invention will becomemore readily apparent to those persons who are skilled in the relevantart, particularly, when such description is taken in conjunction withthe attached drawing figures and with the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of a transit vehicle;

FIG. 2 is a cross-sectional view of the transit vehicle along lines 2-2of FIG. 1;

FIG. 3 is a planar view of the floor panel of the present inventionparticularly illustrating the presently preferred shape of the heatingelement;

FIG. 4 is a partial cross-sectional view of the floor panel of thepresent invention along lines 4-4 of FIG. 3;

FIG. 5 is a partial schematic view of the presently preferred heatingelement construction for use with a floor panel of the presentinvention;

FIG. 6 is a planar view of the floor panel of the present inventionparticularly illustrating an alternative shape of the heating element;and

FIG. 7 is a schematic representation of a presently preferred system forgenerating radiant heat within a transit vehicle.

BRIEF DESCRIPTION OF THE VARIOUS EMBODIMENTS OF THE INVENTION

Prior to proceeding to the more detailed description of the presentinvention, it should be noted that, for the sake of clarity andunderstanding, identical components which have identical functions havebeen identified with identical reference numerals throughout the severalviews illustrated in the drawing figures.

It is to be understood that the definition of a transit vehicle includesbut not limited to rail car, passenger rail vehicle, passenger transitbus, passenger utility bus, school bus, and utility vehicle.

To help the user in understanding the environment in which the presentinvention will be used, a transit vehicle 10, such as a passenger railvehicle, is shown schematically in FIGS. 1-2. Such transit vehicle 10 ischaracterized by a sub-floor structure 12, floor 14, pair of generallyhollow side walls 16, pair of end walls 17 and a roof 18 defining apassenger compartment 20. Plurality of doors 22 are provided within eachside wall 16 for enabling passenger ingress and egress. Plurality ofwindows 24 are further provided within each side wall 16 for passengercomfort and for enabling entry of the natural light into the passengercompartment 20. Plurality of seats 26 are generally positioned adjacenteach side wall 16. A floor cover 28, such as carpet or elastomer, isapplied over the floor 14 for passenger comfort and safety.

The floor 14 may be formed as a single panel or formed from a pluralityof floor panels 30.

According to a first embodiment of the invention, there is provided aheated floor panel, generally designated as 30, and best shown in FIGS.3-5, which includes a core 32 having each of a predetermined size and apredetermined shape. A bottom skin 34 is rigidly attached to a firstsurface 36 of the core 32. A top skin 38 is rigidly attached to theopposed second surface 40 of the core 32.

A heating element 60, having a predetermined size and a predeterminedshape is positioned within a respective groove 42 formed in the secondsurface 40 of the core 32. A top of the heating element 60 isessentially flush with such second surface 40. A pair of ends 61 of theheating element 60 are exposed within at least one cavity 44 formed in apredetermined location of the floor panel 30, best shown by example inFIGS. 3-4 as a peripheral edge.

Such floor panel 30 may be of a type presently employed in theconstruction of the transit vehicle 10, wherein the core 32 is made fromwood, and more particularly a plywood, and the bottom skin 34 and thetop skin 38 are made from metal such as stainless steel. In suchembodiment, a sealant 44 is applied to the surface of the groove 42prior to positioning of the heating element 60 therein to preventmoisture penetration into such core 32. Alternatively, such core 32 maybe made from foam or honeycomb material, which are well known in theart.

Preferably, such floor panel 30 is a composite floor panel 30, whereineach of the core 32, the bottom skin 34 and the top skin 38 is made froma non-metallic material.

One type of such composite floor panel 30 is taught by U.S. Pat. No.6,824,851 to Locher et al and the teachings of such U.S. Pat. No.6,824,851 are incorporated into this document by reference thereto.

In this embodiment the core 32 is a precured reinforced core formed by aplurality of phenolic ribs 46 and a plurality of foam strips 48positioned in an alternating fashion. A pair of side closeouts 50 and apair of end closeouts 52 abuttingly engage the top skin 38 and thebottom skin 34 and surround the core 32, thus substantially defining aperimeter of the floor panel 30. Each of such pair of side closeouts 50and a pair of end closeouts 52 is a fiber reinforced material having athickness that is substantially greater than a thickness of the top skin38 and a thickness of the bottom skin 34.

The material of the top skin 38, the bottom skin 34, and closeouts 50and 52 is a phenolic composite.

To increase heat transfer efficiency of the floor panel 30, a heattransfer compound 56 is disposed within a void formed in the secondsurface 40 of the core 32 after the heating element 60 is positionedwithin the groove 42. By way of example, such heat transfer compound 64is a thermal mastic distributed by Virginia KMP Corporation of Dallas,Tex.

The heating element 60 of a presently preferred embodiment is a seriesresistance constant wattage electric heater 60, best shown in FIG. 5,which includes an electrical conductor 62, an insulation layer 64surrounding the electrical conductor 62, a jacket 56 surrounding theinsulation layer 64 and a metallic braid 68 surrounding the jacket 66.

It will be apparent to those skilled in the relevant art form thatseries resistance two conductor zone heaters, series resistance powerlimiting zone heaters and self regulating electric heaters can beutilized in the floor panel 30 of the present invention.

The presently preferred shape of such heating element 60 is aserpentine.

It is further presently preferred that such floor panel 30 includes asecond heating element 60 a positioned in a second groove 42. It will beappreciated that the second heating element 60 improves reliability ofthe floor panel 30 should the first heating element 60 be mechanicallydamaged during installation of the floor panel 30 or duringmodifications commonly performed within such transit vehicle 10.

Alternatively, as best shown in FIG. 6, the floor panel 80 may include aheating element 90 formed as a pair of parallel spaced bus elements 92oriented in one direction and a plurality of interconnecting elements 94disposed generally perpendicular to such pair of bus elements 92.Accordingly, a groove (not shown) corresponding to the shape of theheating element 90 will be formed within the second surface of a core 82to accommodate such heating element 90.

According to a second embodiment, best shown in FIG. 7, the presentinvention provides a system, generally designated as 100, for generatingradiant heat. Such system 100 includes at least one panel 110 having apredetermined shape and a predetermined size and having at least oneheating element 112 disposed therein. A power source 120 is provided forsupplying a predetermined power and a power switch 122 is operablycoupled intermediately to the power source 120 and one end of the atleast one heating element 112 for selectively providing anddiscontinuing a supply of the predetermined power to the at least oneheating element 112. Preferably, such at least one heating element 112is an electric heating element and such predetermined power is voltage.Such voltage is generally available as either 480 VAC or 600-750 VDC.The other end of the at least one heating element 112 is connected to aground 124. A fuse 126 may he provided for protecting the system 100from excessive current.

The power switch 122 may be manually operable and, preferably, suchpower switch 122 is a well known contactor having a coil 123 and atleast one set of contacts 125 disposed therein and the system 100includes a controller 130 coupled to the coil 123 of the power switch122 and to a control power source 140 for controlling operation of theat least one heating element 112. The controller 130 is preferably amicroprocessor. Based on a predetermined logic, the controller 130selectively supplies a control signal 142 to the coil 123 of the powerswitch 122 causing the at least one set of contacts 125 to close andallow flow of the voltage therethrough in order to activate the at leastone heating element 112 or discontinues the supply of such controlsignal 142 to deactivate the at least one heating element 112.

In combination with the transit vehicle 10, the system 100 may furtherinclude a temperature sensor 144 coupled to the controller 130 forcontinuously providing a temperature signal 146 thereto. Suchtemperature sensor 144 is preferably mounted for sensing the temperaturewithin the passenger compartment 20. The processor 132 disposed withinthe controller 130 is adapted to compare such temperature signal 146against a temperature default stored within a memory 134 and enable thecontroller 130 to selectively supply or discontinue such control signal142. Preferably, a pair of temperatures defaults, one having a lowervalue and the other one having a higher value are stored within thememory 134. Accordingly, the control signal 142 will be provided whenthe temperature signal 146 is about equal to the temperature defaulthaving a lower value and is discontinued when the temperature of thepassenger compartment 20 increases and the temperature signal 146 isabout equal to the temperature default having a higher value.

It will be appreciated that more than one temperature sensor 144 may bemounted in various locations within the transit vehicle 10, eachproviding a distinct temperature signal to the controller 130 which isadvantageous in applications employing zoned heating and having aplurality of distinctly controlled heating elements 112. In suchembodiment, the controller 130 will be capable of providing a pluralityof control signals 142 each received by a respective power switch 142.

Furthermore, at least one externally mounted temperature sensor 148 maybe provided for sensing an ambient temperature and for supplying asecond temperature signal 150 to the controller 130. Such secondtemperature signal 150 may be used for varying the values of thetemperature defaults stored within the memory 134 and, moreparticularly, for adjusting the operating temperature of the passengercompartment 20 according to the existing ambient temperature that mayfluctuate over time.

The system 100 may be further provided with a current monitor 152coupled intermediately to the power source 120 and the power switch 122for monitoring the operating current of the system 100 and for providinga corresponding electrical current signal 154 to the controller 130which is then compared against at least one threshold current signalstored within memory 134 to detect one of normal and abnormal operationof such at least one heating element 112.

The system 100 may further include at least one indicating means 156operable by such controller 130 for indicating at least one of normaland abnormal operation of such at least one heating element 112. Such atleast one indicating means 156 may be one of indicator, light and alarm.Furthermore, the at least one indicating means 156 may be directlyconnected to power switch 122.

Preferably, the design and operation of the at least one heating element112 are carried out to limit the surface temperature of such at leastone panel 110 and associated floor covering 28 at about 125 degreesFahrenheit in order to meet ADA mandate.

According to the third embodiment, therein provided a method forgenerating radiant heat within the passenger compartment 20 of thetransit vehicle 10. The method includes the steps of installing at leastone floor panel having a predetermined shape and a predetermined sizeand having at least one heating element disposed therein. Thenconnecting the at least one heating element to a power switch.Connecting the power switch to a power source of such transit vehiclewhich is capable of supplying a predetermined power. Then operating thepower switch to selectively provide and discontinue a supply of thepredetermined power to the at least one heating element. The method mayinclude an additional step of providing a control means for responsiveto various signals, such as temperature and current, for operating suchpower switch.

It will be understood that the floor construction of the transit vehicle10 employing heating elements to generate radiant heat has a number ofadvantages as compared with conventional baseboard heaters. Removal ofthe conventional baseboard heaters and associated grills simplifies sidewall construction thereby reducing manufacturing costs of such transitvehicle 10 as well as reduces life cycle maintenance costs associatedwith such baseboard heaters. Side wall space occupied by conventionalbaseboard heaters can be now insulated as illustrated by referencenumerals 19 in FIG. 2 to reduce heat energy loss through such side wallsand, more particularly, reduce cost of heating such transit vehicle 10.The maximum temperature of the heating element is set at 125 degreesFahrenheit to meet ADA requirements and in combination with the floorpanel construction eliminates fire hazard associated with conventionalbaseboard heaters. Heated floor area disposed adjacent to each side door22 at least minimizes moisture accumulation and, more particularly,prevent structural floor failures.

Although the present invention has been shown in terms of the heatedfloor panel for use with a transit vehicle such as a passenger railvehicle, it will be apparent to those skilled in the art, that thepresent invention may be applied to other vehicles.

Furthermore, it will be understood that each floor panel may beindividually coupled to the power source of the transit vehicle, may bemechanically and electrically interconnected in series with severalother floor panels into a floor cluster, and may be mechanically andelectrically interconnected in series with all other floor panels withinsuch transit vehicle wherein only the end panels are connected to thepower source.

Thus, the present invention has been described in such full, clear,concise and exact terms as to enable any person skilled in the art towhich it pertains to making use the same. It will be understood thatvariations, modifications, equivalents and substitutions for componentsof the specifically described embodiments of the invention may be madeby those skilled in the art without departing from the spirit and scopeof the invention as set forth in the appended claims.

I claim:
 1. A compartment heating system for a transit vehicle that hasa power supply source and a control power source, the compartmentheating system comprising: a structure that has an interior surface thatis adapted to define a boundary of the compartment, the structure havingan embedded electrically-operated resistive heating element that iselectrically coupled to the power supply source; a power switchconnected in series between the power supply source and the heatingelement, the power switch adapted to provide and discontinue power fromthe power supply source to the heating element; and a controlleroperably coupled to the power switch so as to control the supply ofpower to the heating element, where the controller is powered by thecontrol power source.
 2. The compartment heating system of claim 1wherein the structure comprises a panel.
 3. The compartment heatingsystem of claim 2 wherein the panel is a floor panel.
 4. The compartmentheating system of claim 1 wherein the structure defines at least part ofa floor of the compartment.
 5. The compartment heating system of claim 1wherein the controller selectively applies a control signal to the powerswitch, and wherein the power switch comprises a device that responds tothe control signal and causes the load to be switched.
 6. Thecompartment heating system of claim 1 wherein the heating elementcomprises a pair of spaced, parallel bus members and a plurality ofspaced, parallel members connecting the pair of bus members and disposedperpendicularly thereto.
 7. The compartment heating system of claim 1,further comprising a temperature sensor operably coupled to thecontroller, for providing a temperature signal to the controller.
 8. Thecompartment heating system of claim 7 wherein the temperature sensorsenses a temperature within the compartment.
 9. The compartment heatingsystem of claim 7 wherein the controller includes a memory with apredetermined temperature default stored therein, and wherein thetemperature signal is compared to the temperature default.
 10. Thecompartment heating system of claim 9 wherein the temperature defaulthas a temperature range with an upper value and a lower value.
 11. Thecompartment heating system of claim 7 wherein the temperature sensorsenses a temperature outside of the compartment.
 12. The compartmentheating system of claim 1, further comprising a current monitor inseries between the power supply source and the power switch, wherein thecurrent monitor is operably coupled to the controller, for providing tothe controller a signal indicative of the current supplied to theheating element.
 13. The compartment heating system of claim 1 whereinthe heating element is located under and in close proximity to theinterior surface of the structure.
 14. The compartment heating system ofclaim 13 wherein the structure comprises a covering that defines theinterior surface.
 15. The compartment heating system of claim 13 whereinthe heating element is operated such that the surface temperature of theinterior surface of the structure is limited to no more than about 125degrees Fahrenheit.
 16. A passenger compartment heating system for atransit vehicle that has a power supply source and an independentcontrol power source, the compartment heating system comprising: astructure that has an interior surface that is adapted to define aboundary of the passenger compartment, the structure having an embeddedelectrically-operated resistive heating element located under and inclose proximity to the interior surface of the structure and that iselectrically coupled to the power supply source; a power switchconnected in series between the power supply source and the heatingelement, the power switch adapted to provide and discontinue power fromthe power supply source to the heating element; a controller operablycoupled to the power switch so as to control the supply of power to theheating element, where the controller is powered by the control powersource and not the power supply source; and a temperature sensoroperably coupled to the controller, for providing a temperature signalto the controller.
 17. The passenger compartment heating system of claim16 wherein the structure comprises a covering that defines the interiorsurface.
 18. The passenger compartment heating system of claim 17wherein the heating element is operated such that the surfacetemperature of the covering of the structure is limited to no more thanabout 125 degrees Fahrenheit.
 19. A passenger compartment heating systemfor a transit vehicle that has a power supply source and an independentcontrol power source, the compartment heating system comprising: a floorpanel that has an interior covering that is adapted to define a lowerboundary of the passenger compartment, the floor panel having anembedded electrically-operated resistive heating element located underand in close proximity to the covering and that is electrically coupledto the power supply source; a power switch connected in series betweenthe power supply source and the heating element, the power switchadapted to provide and discontinue power from the power supply source tothe heating element; a controller operably coupled to the power switchso as to control the supply of power to the heating element, where thecontroller is powered by the control power source and not the powersupply source; a current monitor in series between the power supplysource and the power switch, wherein the current monitor is operablycoupled to the controller, for providing to the controller a signalindicative of the current supplied to the heating element; and atemperature sensor operably coupled to the controller, for providing atemperature signal to the controller.
 20. The passenger compartmentheating system of claim 19 wherein the heating element is operated suchthat the surface temperature of the covering of the panel is limited tono more than about 125 degrees Fahrenheit.